Superheater and setting therefor



Feb. 16 1926. 1,572,954

A. D. PRATT SUPERHEATER AND SETTING THEREFOR Filed July 27. 1921 2 Sheets-Sheet 1 Feb. 16 1926. 1,572,954

A. D. PRATT SUPERHEATER AND SETTING THEREFOR Filed July 27 1921 2 Sheets-Sheet 2 INVENTOR Zf /VM ATTORNEYS Patented Feb. 16, 1926. i

UNITED STATES ATENT OFFICE.

ARTHUR n. PRATT, or SHORT HILLS, NEw JERSEY, ASSIGNOB To THE muscocx & wrLcox COMPANY, 0E BAYONNE, NEW JERSEY, A CORPORATION or NEW JERSEY.

SUPERHEATEB AND SETTING THEREFOR.

Application filed July 27, 1921. Serial No. 487,857.

7 '0 all whom it may concern:

Be it known that I, ARTHUR -D. PRATT, a

jected to the rear of the furnace, from whence it ascends into a chamber 34, from citizen of the United 'States, residing at\which the gases pass through the checker- Short Hills, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Super-.

heaters and Settings Therefor. of which the following is a specification.

One of the objects of my invention is the provision of a cheap, compact and eflicient the arts of the superheater, including the bee ers, are enclosed in the setting, and in which the steam flows in series in a generally reverse direction to the flow of gases.

'Where the connections between the sections of the superheater are arranged without the setting, there is a considerable drop in steam pressure, which is objectionable, both because of the decreased efficiency and of an undesirably low pressure of the superheated steam, and-which is particularly objectionable where the superheater handles low pressure steam. ,In accordance with my invention, in which the superheater is entirely enclosed in the setting, the foregoing difficulties are overcome.

While I have described my invention as applicable to a superheater, it will be understood that certain features thereof are applicable to fluid heaters other than superheaters.

My invention will be best understood by U reference to the accompanying drawings, in

which Figure .1 1s a. horizontal sectional viewthrough a superheater and the setting therefor embodying my invention, and

taken along the plane of the line 44 of Fig. 2'; Fig. 2 is a vertical longitudinal section takenthrough Fig. 1; Fig. 3 is a vertical transverse section taken on the line ELike re erence characters indicate like parts throughoutthe drawings.

Referring, now, to the drawings, and first to Figs. 1 to 3, I have indicated, generally,

at 10 asuperheater which .is enclosed by the 3 setting. the front and rear walls of which in the claims as enclosing walls. 1 burner 32 is used for supplying fuel to the furnace. The'flame from the burner is proadjacent intermediate header 17.

work 24 to the superheater 10. An access door is preferably provided for the combustion chamber, and an access door 36 for the chamber 34. Dusting openings 30 are also preferably provided in the wall of the setting opposite the superheater.

The superheater 10, which is located in a space at the rear of the bridge wall 16, comprises headers 17, which are shown as cylindrical in form, and preferably located near the" bottom of the enclosure, and which extend'transverscly across the superheater enclosure. The inlet header 17 is preferably located adjacent to the rear wall 12, the outlet header 17 is preferably located adjacent to the bridge wall 16, and the intermediate headers 17 and 17 are preferably located immediately above partition walls 18, as best shown in Fig. 2. Groups of U-'shaped superheater tubes are connected to successive headers and extend upwardly therefrom longitudinally of the superheater enclosure.

In Fig. 2, three such groups are shown, the first group .19 connecting the header 17 to the adjacent intermediate header 17, the second group 19" connecting the intermediate headers 17 and 17 andthe third group 19 connecting the outlet header 17 to the The adjacent headers of the U-tubes of the various groups are thus connected to the same headers, causing the steam to flow from the groups 19 to the header 17, from the headers 17 directly to the tubes of group 19 and so on to the outlet header 17 whereby steam flows through said tubes and headers in series. The tubes of each group are preferably arranged in a plurality of rows, as best shown in F ig. '1, the tubes of the successive rows preferably being staggered with reference to'each other, as best indicated in Fig. 1. In order to direct the gases longitudinally over the superheater tubes, baflles or walls 20 and 21 are formed by the tubes themselves between the groups 19, 19 and 19 of the superhe'atertubes, the tubes of outer rows of adjacent groups lying side by side to form a continuous baflle. as indicated in Fig. 1. The tubes at the end of the bailie are bent away from each other, as at 22, to form an opening through which the gases pass from one chamber to the next, the tubes bent away from each other.

at the alternate ends of successive bafiles being bent away from each other, as indicated in Fig. 2. In the form illustrated, where there are but three groups of tubes,

there are only two such bafiles and the tubes at opposite ends of the two baflies are thus The baffle 20 extends downwardly from the roof 14 between the groups 19 and 19. the opening 22 being formed between the baffle 20 and the header 17 The second bafiie 21 extends upwardly from the second header 17 between the groups 19 and 19", an opening 23, similar to the opening 22, being formed between the top of the battle and the roof. The intermediate headers 17 and 17 are thus located in the planes of the bafiles 20 and 21. Preferably checkerwork 24 is provided at the top of the bridge wall 16, and extending to the roof 14, to assist in thoroughly mixing the gases and to protect the upper ends of the superheater tubes above the bridge wall from the direct radiant heat of the furnace. The checkerwork is par ticularly useful in protecting the front tubes located adjacent to the combustion chamber when the steam passes through the tubes in series from the rear to the front, as here shown, and where the front tubes are, therefore, operated at a high temperature.

Saturated steam is introduced to the inlet header 17 at 26, a valved outlet pipe for the superheater being indicated at 27.

In operation, the gases from the combustion chamber 34 pass through the checkerwork 24 and downwardly longitudinally of the tubes of the group 19, through the opening 22, upwardly over the group of tubes 19 to the opening 23. and downwardly over the group of tubes 19*, from which they pass through the outlet flue 31. The steam which enters the inlet header 17 a through the inlet pipe 26, passes through the group of tubes 19 to the first intermediate header 17, thence through the group of tubes 19 to the second intermediate header 17, and thence through the third group of tubes 19 to the outlet header 17. The steam thus passes through the tubes and headers in series in a generally reverse direction to the flow of the gases, thereby increasing the efficiency of the superheater. It will also be apparent that by flowing through the tubes and headers of the superheater in series in the manner described, in case the steam is uniformly distributed in the inlet header 17, the uniform distribution of steam throughout the tubes of the superheater will be preserved, and in case of any uneven distribution of steam in the inlet header, the series flow of the steam through the various tubes and headers will tend evenly to distribute the steam to the various tubes as the steam passes in series through the tubes of the headers.

indicated in Fig. 5.

rear of the furnace, from whence it ascends into a chamber 34, from which the gases pass through the checkerwork 24 to the superheater 10. An access door 35 is referably rovided for the combustion 0 amber, an 34. In this form of my invention, I have shown the bafiles 20 and 21 between the groups 19, 19 and 19 of the superheater tubes formed by the tubes themselves, the tubes of outer rows of adjacent groups lying side by side to form a continuous baflle, as indicated in Fig. 4. The tubes at the end of the baflle are bent away from each other, as at 36, to form an opening through which the gases pass from one chamber to the next, the tubes at the alternate ends of successive bafiles being bent away from each other, as In the form illustrated, where there are but three groups of tubes, there are only two such bafiles, and the tubes at opposite ends of the two battles are thus bent away from each other.

What I claim and desire to secure by Letters Patent of the United States is:

1. In a fluid heater and its setting, transverse headers located adjacent to an enclosing wall of the heater, groups of U-shaped tubes connected at their ends to adjacent headers, the adjacent ends of adjacent groups being connected to a common header, some of the tubes of each group being arranged side by side to form a baflie but bent away from each other at alternate ends in successive groups, whereby the gases are directed in series over said groups of tubes.

2. In an independently fired superheater and its setting, transverse headers located adjacent to an enclosing Wall of the superheater, groups of U-shaped superheater tubes connected at their ends to adjacent headers, the adjacent ends of adjacent groups being connected to a common header, some of the tubes of each group being arranged side by side to form a bafiie but bent away from each other at alternate ends in successive groups, whereby the gases are directed in series over said groups of tubes.

3. In an independently fired superheater and its setting, transverse headers located adjacent to an enclosing wall of the superheater, groups of U-shaped superheater tubes connected at their ends to adjacent headers, the adjacent ends of adjacent groups being connected to a common header, some. of the tubes of each group being arranged side by side to form a bafiie but bent away from each other at alternate ends in successive groups to form openings, wherean access door 36 for the chamber by the gases are directed in series over said groups of tubes.

4. In an independently fired superheater and its setting, transverse headers located adjacent to an enclosing wall of the superheater, groups of U-shaped superheater tubes connected at their ends to adjacent headers, the adjacent ends of adjacent groups being connected to a common header,

10 some of the tubes of each group being arranged side by side to form a ba-flle but bent away from each other at alternate ends in successive groups, whereby the gases are directed in series over said groups of tubes, the groups of U-shaped superhe ater tubes being arranged in a plurality of rows with the tubes of successive rows staggered with ref- 1 erence to each other.

ARTHUR D. PRATT. 

